Exercise stick



FIG. 1 is a perspective view of an exercise stick showing my new design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a side plan view thereof;

FIG. 5 is a second side plan view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a second bottom plan view thereof. 

The ornamental design for an exercise stick, as shown and described. 